1. Field of the Invention
The present invention relates to low temperature evaporative clothes dryers. More particularly, the present invention relates to clothes drying cabinets employing circulating drying air from an air dehumidifier.
2. Description of the Related Art
The use of cabinet type clothes dryers is well known, particularly for woolens and delicate items which are harmed by conventional tumble dryers. Also, in locations where energy is at a premium, cabinet dryers may be more energy efficient than conventional clothes dryers. In cabinet dryers the clothes are either hung as in clothes cabinets or laid flat on supports. Such dryers may simply circulate outside air through the cabinet in cases where the outside air is relatively dry. Heaters may also be used to heat the air supplied to the cabinet. In the most sophisticated embodiments, air is at least partially recirculated through the cabinet and a dehumidifier removes moisture from the recirculating air so as to maintain a supply of drying air.
Recirculation insures that heat energy supplied by heaters or the heat added by the condenser of the dehumidifier is retained in the drying cabinet system. Such cabinet systems are preferably made from wood or other insulative material to conserve heat energy in the system. Previous systems do not provide for fully closed recycle of the drying air, allowing for entrance and/or exit of air to the environment. The operation of these systems is dependent on the temperature and humidity of the environmental air. Some systems are not effective in highly humid air or in low environmental temperatures where the evaporator tends to freeze up with ice. They require complicated cooling systems and vents to avoid buildup of heat in the system which would lead to damage of the clothing to be dried. It would be desirable to provide a recirculating air clothes drying cabinet having a closed system which operates independent of the environmental air conditions. Such a system would operate effectively within a wide range of environmental temperatures with minimal energy usage.
European patent document No. 0 094 356 A1, published Nov. 16, 1983, describes a clothes drying cabinet having a drying chamber, a circulating fan, and a heat pump that serves as both a dehumidifier and a heater. The heat pump includes a compressor, a condenser that acts as a heater, and an evaporator that acts as a dehumidifier. Air is circulated by the fan into the cabinet through an inlet, is heated by the condenser, circulated across the clothing in the drying chamber, and directed to a cooling channel where the humidity is removed from the air by the evaporator and allowed to collect in a collection bin.
Japanese patent document No. 40899099, published Mar. 23, 1992, describes a clothes dryer having a main cabinet body, a dehumidifier, and a heater. Air is circulated throughout the system by a fan. A temperature sensor is operated to regulate the temperature in the cabinet body and opens either suction ports or exhaust ports when the temperature in the chamber becomes too high. The clothing may be dried on hangers or on a drying shelf.
U.S. Pat. No. 6,005,227, issued Dec. 21, 1999, to Pappas, describes a towel warmer console cabinet having a circulating fan and an electric heater and teaches that it is known to re-circulate air within the cabinet instead of drawing in ambient air and exhausting humidified air.
U.S. Pat. No. 3,866,336, issued Feb. 18, 1975, to Bereza, describes a cabinet-type laundry dryer and teaches that the heat source may be external to the cabinet such that warm air is directed into the cabinet by a duct from a household heating unit instead of providing a self-contained unit.
U.S. Pat. No. 5,555,640, issued Sep. 17, 1996, to Ou, describes a household drying cabinet having a blower and a heating chamber disposed on the cabinet top, generating forced and heated air downward into a drying chamber.
U.S. Pat. No. 5,870,836, issued Feb. 16, 1999, to Grimes, describes a portable clothes dryer useful in dry climates which unfolds to support a plurality of screen supports for clothing items and includes a fan for circulating dry air around the clothing items.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a low temperature clothes dryer solving the aforementioned problems is desired.